title: The role of echocardiography in predicting responders to cardiac resynchronization therapy.
abstract: BACKGROUND
  This multicenter prospective cohort study aimed to identify both ability of echocardiographic parameters to detect cardiac resynchronization therapy (CRT) volume responders and relation of these parameters with clinical outcomes.
  
  
  RESULTS
  CRT responder was defined as ≥ 15% reduction of left ventricular (LV) end-systolic volume at 6 months. Seven echocardiographic dyssynchrony parameters were evaluated. The clinical endpoint comprised time to death from any cause or unplanned hospitalization for a major cardiovascular event. Of the 217 patients enrolled, 63 percent were classified as volume responders, in whom significantly fewer events occurred than in non-responders (log rank, P < 0.001). No single echocardiographic criterion had significant power to detect volume responders, but a combining measurement of dyssynchrony between septum and LV free wall with M-mode and tissue Doppler imaging was independently associated with volume responders. In addition, this combined parameter was associated with the endpoint (hazard ratio, 0.66, 95% confidence interval 0.30-0.98, P = 0.04). In contrast, left bundle branch block was identified as an independent predictor of volume responders and more strongly associated with the endpoint (hazard ratio, 0.38, 95% confidence interval 0.20-0.72, P = 0.003).
  
  
  CONCLUSIONS
  Echocardiographic parameters did not show significant power to detect CRT responders independently.
authors.affiliation: Cardiovascular Division, Institute of Clinical Medicine, Graduate School of Comprehensive Human Science, University of Tsukuba, Tsukuba, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Seo
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ito
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nakatani
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Takami
authors.forename: Shigeto
authors.initials: S
authors.lastname: Naito
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Shiga
authors.forename: Kenji
authors.initials: K
authors.lastname: Ando
authors.forename: Yuji
authors.initials: Y
authors.lastname: Wakayama
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Aonuma
mesh_terms: D058406:Cardiac Resynchronization Therapy; D015331:Cohort Studies; D004452:Echocardiography / Q000379:methods*; D006801:Humans; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000628:therapy